CROSS-REFERENCES TO RELATED APPLICATIONS
This application is related to Japanese Patent Application No. Hei 9(1997)-132466, filed on May 22, 1997 whose priority is claimed under 35 USC Section 119, the disclosure of which is incorporated herein by reference in its entirety.
1. Field of the Invention
The present invention relates to a method for manufacturing a suspension element for a magnetic head, and more particularly to a method for mass-producing suspension elements by allowing a plurality of processing sections to sequentially perform necessary processing steps while conveying a band-shaped sheet(substrate) by means of rolls.
2. Description of the Related Art
In a magnetic disk device for a computer, a so-called CSS (Contact Start Stop) method has generally been employed in which an actuator positions a magnetic head on a desired track of a rotating magnetic disk to read and write data to the disk.
In this method, the magnetic head is supported on a tip of an arm of the actuator through a plate-shaped elastic supporter which is referred to as a suspension element. When the disk rotates, the magnetic head is allowed to float with a very small gap above the disk as a result of a balance of floating force of an air fluid generated by rotation of the disk and elastic force of the suspension element against the disk. When the disk stops, the actuator moves the magnetic head to a specified region on the disk so that the magnetic head comes in contact with the disk.
Such a suspension element supporting the magnetic head must contain a plurality of signal wiring lines on the surface for reading and writing data from the magnetic head. In order to manufacture the suspension, therefore, a so-called batch processing method has conventionally been employed in which an insulating layer is formed on a surface of a square metal substrate and a pattern of wiring lines is formed on the insulating layer, that is, the substrate is subjected to various film forming processing steps in a fixed state (for example, see Japanese Unexamined Patent Publications Nos. Hei 6(1994)-215513, Hei 7(1995)-57418, Hei 7(1995)-235156 and Hei 7(1995)-262541).
There exists a rapidly growing demand for high efficiency suspension elements. The batch processing method using a fixed substrate is not a well-suited manufacturing method for mass production of suspension elements. It is preferable that a band-shaped sheet should be used as a substrate and be processed without a break by a manufacturing line in which a plurality of processing sections are continuously arranged from an inlet of the line to an outlet thereof.
In such a manufacturing line, however, the band-shaped sheet is continuous from the inlet of the whole line to the outlet thereof. Therefore, there have been the following problems.
(1) It is necessary to strictly make processing capabilities (speeds) identical with each other in the processing sections.
(2) If a part of the processing sections breaks down, all the processing sections should be stopped for repair. Consequently, a manufacturing efficiency is reduced.
(3) Also in the case where a part of the processing sections becomes defective, the whole sheet is affected so that a yield of products is greatly lowered.
(4) No part of the processing sections can perform a batch processing.